Xwtlhelm k khopff



Feb. 10, 1931. w. KRQPFF 1,791,899

CASH REGISTER Filed June 19. 1929 gin mantel Wilhelm Kropfl PatentedFeb. 10, 1931 warren STATESPATET OFFICE WILHELIH KROPFF, F BERLIN,GERMANY, ASSIGNOB THE NATIONAL CASH REGISTER COMPANY, OF DAYTON, OHIO, ACORPORATION OF MARYLAND oAsn: n-ners'rnn 7 Application filed June s,1929, Serial No. 372,034, and in German July a0, 1928.

This invention relates to registers and like machines, and moreparticularly refers to improvements in printing mechanisms for suchmachines. The invention is an improvement on, and is illustrated hereinin connection with a printing mechanism of the type disclosed in LettersPatent of the United States, No. 1,761,556, granted June 3, 1930, to

Charles H. Arnold. y

The printing mechanism disclosed in the above-mentioned patent isapplicable to many of the conventional types of cash regis ters and isadapted to print on an inserted slip. An impression hammer is adapted todeliver two impression blows at each operation of the machine,regardless of whether a slip is in printing position or not. Theprinting hammer of the Arnold printer is normally cocked, beingretracted at the end of each operation of the machine, normally sethammer driving means being provided to cause the hammer to deliver twoimpression blows. If there is no slip in printing position in themachine to receive the impression, the blows fall upon the type wheels,causing a smudge on the platen, which, on a subsequent operation, istransferred to the reverse side of the slip when inserted.

It is, therefore, an object of this invention to provide a printingmechanism of the type indicated, with a novel feeler controlled hammerdisabling means to prevent operation of the hammer if no slip or otherrecord material is in printing position to take the imprint from thetypes.

Another object is to provide a machine of the class described with anovel, flexible trip ping means for the hammer drivers.

A further object .of this invention is to pro: vide a novel means undercontrol of an insert able record material, to normally prevent operationof the printing hammer.

Vith these and incidental objects in view,

the invention consists of certain novel features of construction andcombinations of parts, the essential elements of which are set forth inappended claims and a preferred form or embodiment of which ishereinafter described with reference to the drawings type wheels 30,rotatively mounted on a shaft 81, supported in aframe 32. In thisparticular instance,the frame 32 represents the left side frame of anyconventional cash register. The type wheels are secured-to the ends ofnested tubes, not shown, and are adapted to be differentially rotatedunder the control of manipulative evices such as, for instance,

depressible keys, etc.. to bring the desired' type to the printing line,in the well known manner.

After the type wheels are positioned, it is desired to take impressionstherefrom on an inserted slip. To accomplish this, a platen 33 carriedin a pair of swinging hammer arms 84, only one of which appears in thedrawings, journaled on a stud 35 projecting from the side frame 32, isdriven against the types at the printing line, on each operation of themachine. The slip is not illustrated in the drawings, but may compriseany suitable sales slip or other record material. A chute 36 aperturedat points in line with the printhammer and the types at the type line,is providedto receive the record material and hold it in the properposition to receive the impression. An ink ribbon, not shown, is usuallyprovided betweenthe platen 33 and the typecarriers 30, to render theimprint pressing the cross rod 71 against the longer arms of apair ofhammer-driving elbow levcrs'i'z and 3 pivoted side by slde on the hammerstud 35 projecting from the side frame 32.

A hammer restraining and restoring bail 74 carried by arms fast on arestoring shaft 37 journaled in the side frame 32, normally lies in thepaths of the shorter, inclined arms of the driving elbow levers 72 and73 to hold the latter in their fully retracted positions against thetensions of their respective drive springs 76 and 77, which tend to rockthe driving elbow levers count-er-clockwise.

Springs 78 and 79 press the hooked ends of detents 90 and 91 pivoted onthe restoring shaft 37 against the free ends of the longer arms of thedriving elbow levers 7 2 and 73. respectively, to latch the latter intheir cocked positions. The restraining bail 74 normally sustains thestrain of the strong drive springs 7 G and 77 to relieve the detents 90and 91 of strain, the bail restoring the drive levers sufiiciently toleave a slight clearance between the longer arms of the drive levers andthe detents 90 and 91 when the latter are in effective positions.

Means to hold the hammer restraining and restoring bail 74 in, andrestore it to its normal position wherein it holds the hammer drivinglevers 72 and 73 in cooked or set positions includes a pair of cams 38and 39 hubbed together and fast on the usual printer drive shaft 40journaled in the side frame 32, and in a printer frame (not shown). Theprinter drive shaft 40 is given one complete rotation at each operationof the machine in the customary manner.

The cams 38 and 39 wipe against projections 41 and 42 on the divergingarms of a rocker lever 43 fast on a short shaft 44 ournaled in the sideframe 32 and in the printer frame (not shown).

The cams 38 and 39, acting on the projections 41 and 42, rock the lever43 clockwise in three separate steps of movement, there being a briefdwell between the steps, and then counter-clockwise to normal in asingle movement, to rock the restoring shaft 37 first clockwise torelease the hammer-driving levers 72 and 73, and then counter-clockwiseto normal to restore the drive levers to cocked positions.

The clockwise rotation of the restoring shaft 37 likewise comprisesthree distinct steps of movement, and its return movement incounter-clockwise direction is completed in one continuous movement.

Briefly, the purpose of the intermittent clockwise movement of therestoring shaft 37 is to first release the hammer driving levers 72 and73, so that they are held cocked only by the detents 90 and 91, and thento successively trip the detents to enable the drive springs 76 and 77to rock the driving levers successively to cause the hammer 34 todeliver two blows against the types. The releasing and trippingmechanism is fully disclosed in the above Arnold Patent No. 1,761,556,to which reference may be had for a complete understanding thereof, andas this mechanism is not pertinent to the instant invention, no furtherdescription thereof need be given herein.

In the Arnold patent, a link 89 (Fig. connects an arm 86 fast on a shaftcorresponding to the short shaft 44 in the present case with an arm faston a shaft 68, corre sponding to the restoring shaft 37 of the presentinvention. By this arrangement of parts, however, all movements of theprinter drive shaft 82 are transmitted by the link 89 to the shaft 68 toeffect the operation of the hammer at each operation of the machine,regardless of whether or not there is a slip in the proper printingposition in the chute 36 to receive the impression blows of the hammer.

In the present invention, however, the connection between the shafts 44and 37 is a yielding or flexible one, so that the restoring shaft 37 maybe locked against rocking movement when no slip is in the machine, whilethe shaft 44 is rocked idly by the cams 38 and 39.

To this end, a crank 51 fast on the shaft 44 arries a stud 50 whichprojects through a slot 52 formed intermediate the ends of a link 53,the upper end of which is pivotally connected to an arm 54 fast on therestoring shaft 37. A spring 55 connects the stud 50 with a pin 56projecting from the lower end of the link 53, which extends aconsiderable distance beyond the stud 50, thereby forming a flexibleconnection between the crank 51 and the link 53, so that when the link53 is locked against movement, and the crank 51, under the influence ofthe cams 38 and 39, may rock idly, the stud 50 moving up and down withinthe slot 52. The link 53 and the restoring shaft 37 are moved flexiblyby the spring 55 in clockwise direction under the control of the cam 38.However, the restoring movement of these parts, that is, their movementin counter-clockwise direction, is effected positively by the stud 5Opressing against the bottom of the slot 52 under the control of the cam39.

If desired, a hooked latch 57 may be fastened on the restoring shaft 37,and arranged to normally engage a stud 58 projecting laterally from thehammer arm 34 to insure that the hammer remains in its retractedposition. Clockwise movement of the restoring shaft 37 however,disengages the latch 57 from the stud 58, thereby freeing the hammer foroperation. The latch may be dispensed with without affecting theinvention herein set forth.

To enable the operating mechanism for the printing hammer to becontrolled by the presonce or absence of record material in the chute36, there is provided a shouldered restraining arm 59 pivoted on a stud6O projecting from the flexible link 53, to cooperate with a wedgeshapedstud 61 projecting laterally from the side frame 32, and normallyrestraining the link 53 and the restoring shaft 37 in their normalpositions against movement.

Means under the control of an insertable slip operates to disengage therestraining arm 59 from the stud 61, thereby permitting actuation of thehammer driving mechanism only on those operations of the machine when aslip is inserted in proper position in the chute 36. This releasemechanism for the arm 59 comprises a feeler finger 62 journaled on thehammer supporting stud 35 and connected by a yoke 63 to a release finger64, also journaled on the stud 35. The feeler finger 62 projectsdownwardly through an opening in the slip chute 36, and across the pathof, the slip. When no slip is in the machine, the feeler finger 62normally rests against the edge of the opening in the chute 36, therebylimiting the counterclockwise movement of the feeler finger. The freeend of the release finger 6 L normally extends beneath the free end ofthe restraining arm 59, or of a stud 65, projecting laterally from therestraining arm. Insertion of a slip into the chute 36 rocks the feelerfinger 62 in clockwise direction to rock the release finger 64: alsoclockwise, which latter, acting on the restraining arm 59, raises thelatter to free it from the wedge-shaped stud 61, thereby freeing thelink 53to the action of the spring 55, so that, upon rotation of thecams 38 and 39 which rock the shaft 14: and

'crank 51 clockwise, the spring will draw j is fully disclosed in theabove-mentioned Arnold Patent No. 1,761,556.

As stated above, the counter-clockwise movement of the shaft 44: and thecrank 51 with its stud 50, draws the yielding link 53 positivelydownwardly to rotate the restoring shaft 37 in counter-clockwisedirection and restore the parts to. their normal positions. The link 53draws the restraining arm 59 therewith until the shoulder thereon is inposition to drop over the wedge-shaped stud 61. The engagement of therestraining arm 59 with the stud 61, however, is delayed until the slipis removed from the chute 36 after the completion of the operation,whereupon the feeler finger 62 and the release finger 64 rock by gravityin counter-clockwise direction about the hammer shaft 35, to enable therestraining arm 59 to swing downwardly to fit its shoulder against thestud. 61. In this position the restraining arm' 59 looks the link 53against rising, and-hence locks the restoring shaft 37 against releasingthe hammer driving levers 72 and 73.

While the form of mechanism herein shown and described is admirablyadapted to fulfill the objects primarily stated, it is to be understoodthat it is not intended to confine the invention to the one form orembodiment herein disclosed, for it is susceptible of em bodiment invarious forms all coming within the scope of the claims which follow.

What is claimed as new, is

1. In a machine of the class described; the combination with typeelements; aprinting hammer to take impressions from thetype elements;and means to operate the hammer; of a latch normally in position torestrain the hammer against operation;

means operable at-eachoperation of the macombination with type elements;a hammer to take impressions therefrom; and hammer driving mechanism; ofmeans to control the hammer driving mechanism, including a yieldabletransmitting connection; means to lock the connection in normalposition; and means controlled by the presence of record material todisable the locking means.

3. In a machine of the class described, the combination with typeelements; a hammer to take impressions therefrom; and hammer drivingmechanism; of means to control the hammer driving mechanism, including arestraining and restoring member; an actuator; a fiexible linkage toconnect the actuator and the restraining and restoring member; anormally effective locking means to prevent effective operation of thelinkage; and means to disable the locking means.

4. In a machine of the class described; the combination with typeelements; a hammer to take impressions therefrom on an insertable recordmaterial; and hammer-driving mechanism; of means to control the hammerdriving mechanism, including a shaft; an arm on the shaft; a linkpivoted to the arm; flexible means to operate the link; a locking stud;and a shouldered arm on the link cooperating with the locking stud tonormally restrain the link against movement by its flexible operatingmeans.

5. v In a machine of the class described; the combination with typeelements; a hammer to take impressions from the type elements on aninsertable record material; and means to drive the hammer; of means tocontrol the hammer driving means, including a rock shaft; a linkoperatively connected to the shaft to rock said shaft; yielding means tooperate the link; a locking stud; a shouldered arm on the link tocooperate with the stud and normally look the link against operation;and means under the control of the insert able record material to renderthe shouldered restraining arm ineffective.

6. In a machine of the class described; the combination with typeelements; a hammer to take impressions from the type elements on aninsertable record material; and means to drive the hammer; of means tocontrol the hammer driving means, including a power-transmitting member;and drive means therefor, one of which is yieldable relatively to theother; a stationary element; a shouldered arm on the member engageablewith the stationary element to normally restrain the member againstoperation; a feeler finger under the control of the insertable recordmaterial; and a release finger operated by the feeler finger to disablethe shouldered restraining arm and free the hammer drive controllingmeans for operation.

In testimony whereof I afiiX my signature.

WILHELM KROPFF.

